A 25Gbps low-voltage waveguide Si-Ge avalanche photodiode

We demonstrate a waveguide Si-Ge avalanche photodiode with a breakdown voltage of −10V, a speed of 25GHz, and a gain-bandwidth product of 276GHz. The APD optical receiver achieved sensitivities of −25dBm and −16dBm at 12.5Gbps and 25Gbps at 1550nm, respectively.